[ I'm assuming the HTML entities (e.g. «ü») are really the represented character («ü») encoded using UTF-8 in your source. ]

Remove the ">". That tells open how to open the file. binmode is choking on it.

binmode STDOUT, ":encoding(UTF-8)";
print $s;
[download]

use open ':std', ':encoding(UTF-8)';  # binmodes STD*
print $s;
[download]

By the way, «use Encode;» is not required here.